Originally, this was the electronic egg-shaped
toy from Japan. (Sooooooo
1997!) It was the first in the trend of virtual pets.
Now the word can be used in a different manner. It can be used to describe a person. When calling someone a "Tomagotchi," you're basically saying that they're needy. Usually needy in an annoying fashion. This, of course, pays homage to the original
toy's constant beeping due to wanting virtual
food or other things...